Vtol aircraft



P. G. KAPPUS April 6, 1965 VTOL AIRCRAFT Filed Sept. 6, 1957 7 4 z 1 1 ""0 l l l l lufl I I I I w 0 2 II. w 2 m Z a h w y m 2. z a

United States Patent 3,176,934 VTOL AIRCRAFT Peter Gottfried Kappus, Cincinnati, Ohio, assignor to General Electric Company, a corporation of New York Filed Sept. 6, 1957., Ser. No. 682,327 6 Claims. ((11. 244-12) The present invenion relates to a VTOL aircraft and more particularly to the combination of a novel propulsion system with such aircraft which is capable of propelling the aircraft in normal fashion at supersonic speed and is also capable of providing vertical lift to permit vertical take-off.

The VTOL or vertical take-off and landing aircraft, as such, is not new. Many types have been proposed over the years and a few have been successful. More recently,

' with the advent of the jet engine, VTOL aircraft employing jet engines have been studied and produced. In conventional normal flight, a jet plane requires rather long runways for take-oft and landing maneuvers. Some proposals have disclosed aircraft in which the jet engines are rotatable within the wings so that they may exhaust directly downwardly for vertical lift and then be rotated into a horizontal position for normal flight. Generally speaking, to applicants knowledge, these kinds of aircraft have not been very successful due to the very high fuel consumption in hovering flight. Other proposals have offered the so called flying bedstead or coleopter type VTOL aircraft which offers promise for certain missions. However, the main drawback appears to have been in the conception of a practical aircraft which is suitable for both conventional and for vertical take-off and high subsonic and preferably supersonic horizontal speeds. While achieving these desired characteristics in an aircraft, a system is required that is both feasible and econom ical within the limits of the mission to be accomplished by the aircraft. At the same time, such a system must be relatively simple and straightforward because of weight problems. One proposal, that is well known, employs an engine which drives an auxiliary air compressor by means of gear reduction mechanism to supply air to turbofans lying within the wings. A number of energy conversions are thus required and, of course, with every energy conversion there is a loss present. However, this type of VTOL aircraft aircraft appears promising and, it is this type that the instant invention improves upon.

The main object of the present invention is to provide a VTOL aircraft that requires the minimum of equipment and consequently light weight design that is capable of satisfactory and economical vertical take-off and high subsonic or supersonic operation.

I V A further object of the invention is to provide such an aircraft that minimizes the number of energy conversions that are required for both horizontal and vertical flight.

A further object is to provide such an aircraft that converts directly the small high energy mass flow of the primary engine into a large low energy mass flow in the wing engines with a consequent reduction in the amount of fuel consumed during hovering flight.

Still a further obiect of the invention is to provide such an aircraft which permits very high thrust to be obtained in hovering flight at a moderate specific fuel consumption and permits the considerably lower thrust required for horizontal flight at a higher specific fuel consumption than is required in the normal use of one and the same power generator for both horizontal flight and hovering flight.

Briefly stated, in accordance with my invention, It provide a VTOL aircraft which, in high speed flight, is propelled by a conventional turbojet type engine or suitable gas generator, with or without reheat, and controlled in the conventional manner. For hovering flight and for vertical take-off and landing, the high pressure gas pro- 3,176,934 Patented Apr. 6, 1965 duced by the turbojet engine is diverted, instead of entering the tailpipe, into turbofan unit-s located inside the wing structure. No intermediate energy conversions are required. The high pressure gas is utilized in these wing units to drive high mass flow preferably single stage ducted fans for vertical or substantially vertical lift. Thus the small high energy mass flow of the primary engine is converted into a large low energy mass flow in the wing units.

My invention will be better understood from the following description taken in connection with the accompanying drawing and its scope will be pointed out in the appended claims.

in the drawing:

FIGURE 1 is a partial cross sectional plan view of an aircraft utilizing the novel powerplant of the instant invention with the conventional tail unit partially cut away.

FIGURE 2 is a partial cross sectional view of an axial flow wing unit and,

FIGURE 3 is a view similar to FIGURE 2 showing a radial flow type wing unit.

Referring first to FIGURE 1, there is shown a plan view of the VTOL aircraft of the instant invention which includes a conventional fuselagell) with its tail unit as partially shown and having a pair of wings 11 extending therefrom which wings may be of any suitable form including the swept back type shown for high supersonic forward flight. For normal forward flight fuselage 10 has supported therein a gas generator generally indicated at 12 which may conveniently be in the form of a turbojet engine and more particularly, an axial flow turbojet engine although not being limited to a particular gas generator. The term fuselage is intended to cover the body in which the gas generator is mounted. The engine has a compressor section 13, a combustion section 14, and a turbine section 15. For propelling the aircraft in horizontal flight, a duct connects the engine with a nozzle 16 at the tail unit end of the fuselage. Nozzle 16 may be of any suitable well-known form and will normally be of the variable area type. In order to provide for thrust augmentation or reheat operation, additional fuel injection means 17 may be provided in the tailpipe 18. Tailpipe 18 forms a connecting duct between the nozzle and gas generator. The powerplant thus far described is any conventional powerplant of the jet engine type for normal forward or horizontal flight whether fuselage or wing mounted.

To provide for vertical take-off or direct lift for takeoff from the ground where no substantial forward speed is available for conventional take-off, I provide large low energy mass flow units such as turbofans generally indicated at 19 which are mounted in the plane of the wings 11 for rotation about an axis substantially perpendicular to the plane of the wing. The term wing is intended to cover the body in which the fans are located. Obviously one or more turbofans may be employed in each wing as required. The function of the turbofans is to induce a large mass of ambient airflow through the Wings from the top surface to the bottom to provide vertical lift as will be apparent from the drawing. To this end, as may be seen in FIGURE 2 the'turbofan unit includes a large fan 20 having multifan blades 21 thereon and being suitably supported in the wing by means not shown for rotation therein. The fan is turned or driven by means of a concentric turbine consisting of turbine buckets 22 mounted on the periphery of the fan blades. Suitable shroud means 23 separate the blades and buckets. As

that while I'have illustrated the turbine buckets as being apparent from the showings of FIGURES 2 and 3. The

gas'for driving the turbofans is obtained directly from the main engine 12 by suitable conduits 24which connect the interior of the duct with the wing turbines, this connection being downstream of the main engine to intercept the engineexhaust gas. Conduits 24 direct the exhaust gas intoa-irianifold or'scroll 25' which directs it into turbine nozzle 26 where the gas is passed to the turbine buckets to drive the fan in wing conduits 2 7. An axial type turbinefis shown :in FIGURE 2 and a radial type turbine is shown in FIGURE '3. Either type unit may be successfully employed.

For normal forward flight the Wing units are inoperative and the main engine exhaust is directed through nozzle 16. Horizontal flight is provided for by means such as valve means'zs'which may be pivotally attached a 4 thereon with a nozzle at said unit end and a separate wing extending laterally from each side of said fuselage: a separate generally circular duct extending vertically through each wing, a multi-bladed fan mounted for free rotation axially in said duct, pivoted angular discharge control vanes in each duct outlet and movable between open and closed position to direct the angle of discharge of fluid from vertical to shut off through said duct,-'a turbine operatively connected to drive said fan, jet engine means operatively mounted in said aircraft, a tail pipe interconnecting the jet engine means and nozzle for normal rearward thrust, scroll means having an inlet at said to the fuselage or duct interconnecting the gas generator 7 and nozzle for closing off conduits 24 and permitting exhaust gases to flow directly to the propulsion nozzle 16.

In addition, when the conduits 24 are blocked, the turbofan wing units are also blocked to present a smooth wing surface by means of gates which may takethe form as shown in FIGURE 3 and are pivoted to close over the opening of conduit 27 or, may be in the form of louvers as shown in FIGURE 2' which are rotated to closed position.

In vertical take-off whenthe thrust is downwardly, it is desired to have some means of control as to upward direction so that the'thrust may be directly downward or at an angle to the ground. This is obtained by the use of control va'nes"30 mounted on the lower wing surface andmovable to provide direction ,to the fan discharge. These 'vanes maybe conveniently in the form of flaps which are pivoted to'the wing surface at 31 to permit rotation'to any desired angle.

The operation of the aircraft will be apparent from the above description.

2. Apparatus as described in claim 1 wherein said turbine means operatively connected to drive said fan\ and said fan comprise a common wheel.

3. Apparatus as described in claim 1 wherein said turbine means comprises a row of turbine buckets mounted on the periphery of said fan.

4. Apparatus as described in claim 3 and having at least the inlet to said'turbine disposed in substantially the same plane as the fan, andsaid scroll outlet having its center plane lying substantially in the plane of said fan.

5. In an aircraft having a wingz'a generally. circular duct extending vertically through said Wing; a multibladed. fan mounted for free rotation axially in 'said duct; ,a turbine operatively connected to said fan; a jet engine operatively mounted in the aircraft and having a tailpipe disposed in the aircraft for normal rearward thrust; a scroll having an inlet at said tailpipe and an outlet adjacent said turbine, said outlet extending circum- 'ferentially around a'portion of said turbine and being shaped to direct exhaust gases through said turbine into said duct; and means in said tailpipe to divert at least tively rotated to divert the exhaust 'gas downstream of the I engine, with no intermediate conversion, into conduit 24 driving the tip turbines and, the wing fans. At the same time gates 29 will be opened and control vanes 30 will be suitably oriented to give the desired angle of vertical lift. A large low energy masslflow of ambient air is thus induced by fans 20 which are driven directly by the small highenergy mass flow of the main engine to provide vertical lift. V

Thus thef .present invention avoids energy losses, in

a portion of'the engine exhaust gases intosaid'inlet.

6. In an aircraft having a wing: a generally circular .duct extending vertically through said wing; a multibladed fan mounted for free rotation axially'in said duct; aturbine operatively connected to said fan adjacent to the periphery thereof and having at least the'inlet thereto disposed in .substantially the same plane as the fan; a jet engine operatively mounted in the aircraft and having a tailpipe disposedin the aircraft for normal rearward thrust; a scroll having an inlet at said tailpipe and an outlet adjacent to said turbine inlet, said scroll outlet having its center plane lying substantially in the plane of said fan to direct exhaust gases in the plane of said fan, said outlet extending circumferentially around at least a portion of said turbine and directing the exhaust converting from one form of energy to another and utilizes the main engine'exhaust directly by the wing turbofans for vertical lift and, selectively, by the propulsion ,nozzle for forward flight which permits high subsonic and supersonic forward flight.

While a particular embodiment of the invention has What I'claim as'new'and desireto secure by Letters 7 Patent'of the United States is: r

" '1Q'Iniau ,airctaftphaving a fuselagerwith. a tailunit been illustrated and described, it will be obviousto those skilled in the art that various changes and modificatlons gases throughsaid turbine into said duct; and means in said tailpipe to "divert at least: a portion of the engine exhaust gases" into said' scroll inlet.

References Zited by the Examiner MILTON BUCI-ILER, Primary Examiner {MILTON L,iMARLANDQEMILEPAUL, R. DAVID BLAKESLEE, Examiners. l y 

1. IN AN AIRCRAFT HAVING A FUSELAGE WITH A TAIL UNIT THEREON WITH A NOZZLE AT SAID UNIT END AND A SEPARATE WING EXTENDING LATERALLY FROM EACH SIDE OF SAID FUSELAGE: A SEPARATE GENERALLY CIRCULAR DUCT EXTENDING VERTICALLY THROUGH EACH WING, A MULTI-BLADED FAN MOUNTED FOR FREE ROTATIUON AXIALLY IN SAID DUCT, PIVOTED ANGULAR DISCHARGE CONTROL VANES IN EACH DUCT OUTLET AND MOVABLE BETWEEN OPEN AND CLOSED POSITION TO DIRECT THE ANGLE OF DISCHARGE OF FLUID FROM VERTICAL TO SHUT OFF THROUGH SAID DUCT, A TURBINE OPERATIVELY CONNECTED TO DRIVE SAID FAN, JET ENGINE MEANS OPERATIVELY MOUNTED IN SAID AIRCRAFT, A TAIL PIPE INTERCONNECTING THE JET ENGINE MEANS AND NOZZLE FOR NORMAL REARWARD THRUST, SCROLL MEANS HAVING AN INLET AT SAID TAIL PIPE AND AN OUTLET ADJACENT SAID TURBINE, SAID OUTLET EXTENDING CIRCUMFERENTIALLY AROUND A PORTION OF SAID TURBINE AND BEING SHAPED TO DIRECT EXHAUST GASES THROUGH SAID TURBINE INTO SAID DUCT, AND MEANS IN SAID TAIL PIPE TO DIVERT AT LEAST A PORTION OF SAID ENGINE EXHUAST GASES INTO SAID INLET. 